JSON Formatter
Format, minify, and validate JSON instantly by pasting your data.
Pretty-print JSON with consistent indentation or minify it to reduce size, then copy the output with a single click.
This tool helps you quickly detect syntax errors and verify JSON structure, making it ideal for debugging API responses, configuration files, and test data.
Clear formatting improves readability, while minified output is useful
for transmission and storage.
All processing is performed directly in your browser.
No JSON data is sent to any server, ensuring a fast and secure experience
for developers and anyone working with structured data.
JSON Formatter and Validator
JSON is used everywhere in APIs, configuration files, logs, fixtures, and NoSQL documents, but a single missing comma or quote can break parsing. This browser-based JSON formatter helps you paste JSON, make it readable with indentation, and check syntax errors without sending the data to a server.
Common use cases
- Inspect API responses: Turn minified JSON into a readable tree-like structure for debugging.
- Validate configuration files: Catch syntax errors before deploying JSON-based settings.
- Prepare review snippets: Format JSON before sharing it in issues, pull requests, or documentation.
Things to watch
JSON does not support comments, and values such as "1" and 1 are different types. When you format or validate JSON, also check whether strings, numbers, booleans, arrays, objects, and null match the API or configuration schema you expect.
Articles for this tool
CSV and JSON Conversion: Choosing the Right Format for APIs and Data Migration
Learn how to convert between CSV and JSON safely, including headers, delimiters, value types, nested data, and practical workflow tips.
JSON Formatting and Validation: How to Read API Responses Safely
Learn how to format JSON, catch syntax errors, inspect value types, and turn API responses into types, schemas, or documentation.
Mastering the JSON Ecosystem: Best Practices for Type Safety and Schema Management
JSON is more than just a data format; it's the backbone of modern development. From TypeScript types and Zod validation to OpenAPI documentation, learn how to leverage the modern JSON ecosystem.
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